Based on what?!?
I'm here in the Silicon Valley, and my experienced American Citizen engineering friends are going years between jobs!!
Meanwhile, foreigners flood this place, and radically change the culture, the morals, and even the language.
You stop all legal immigration and the US economy will go to the toilet. Many foreign firms wanting to set up headquarters in the US would effectively be prevented from doing so.
Stop with the rhetoric. Answer my question. Do you want all legal immigration blocked?